1. Field of the Invention
The present invention relates to an image forming apparatus, a control method for the same, and a storage medium storing a program.
2. Description of the Related Art
With image forming apparatuses, there are cases where paper jamming (i.e., jamming) occurs in the complex mechanism therein while image formation is in progress. Because of this, the image forming apparatus is provided with a jam detection sensor for detecting jams in the engine unit, and is configured such that if jamming is detected by the sensor, an image forming operation is interrupted and a user is notified of the jamming. Accordingly, due to the user removing the jammed paper and the like and causing the image forming apparatus to return from the jammed state to a normal state, the image forming apparatus again enters a state in which it is possible to execute the image forming operation.
However, even if jamming occurs, there are cases where the power source of the image forming apparatus is powered off by a user operation performed while the cause of the jamming has not been eliminated and the jammed state still exists. In such a case, the image forming operation cannot be performed while in the jammed state, and therefore, with a general image forming apparatus, notification of jamming will be made once again when the power source of the image forming apparatus is switched on the next time.
In order to realize this function, with a conventional image forming apparatus, a jam detection sensor is used to detect whether or not jamming has occurred when the power is switched on, or the fact that jamming occurred is stored in a non-volatile storage device and notification of the jamming is made based on the stored content the next time the power source is switched on. For example, Japanese Patent Laid-Open No. 2003-118881 discloses a technique in which the fact that jamming occurred while image formation was in progress is stored in a non-volatile storage device. Then, when the image forming apparatus is powered off without a jam countermeasure being taken, notification of the fact that jamming occurred is made based on the content stored in the non-volatile storage device when the image forming apparatus is powered on the next time.
On the other hand, in recent years, interest in power conservation in image forming apparatuses has been increasing. In view of this, in order to suppress power consumption in image forming apparatuses, there are image forming apparatuses that include power-saving functions for energizing only areas that are needed for image forming operations for only the necessary amount of time. With image forming apparatuses that include these power-saving functions, in order to further reduce the power consumption of the overall image forming apparatus, startup is performed without energizing an engine unit when the image forming apparatus is activated. Then, by energizing the engine unit for the first time at the point in time when an image formation operation is instructed and de-energizing the engine unit once again when the formation operation is complete, the time period during which the engine unit is energized, which consumes a large amount of power, is made as short as possible and power consumption is suppressed.
In this kind of image forming apparatus, if the image forming apparatus is powered off while in the jammed state, the engine unit is not immediately energized as stated above when the image forming apparatus is powered on the next time. Accordingly, since the engine unit is not energized when the power source is switched on, the jam detection sensor cannot detect the jamming at that point in time, and the earliest time at which the jam detection sensor can detect the jamming is the point in time when the start of the image forming operation is instructed. In other words, even if jamming has occurred, the user cannot be notified of that fact when the image forming apparatus is started up.
If jamming occurs, it is desirable that the user is notified to that effect immediately when the image forming apparatus is started up. This is because it is time-consuming to resolve a jammed state, and noticing the jamming for the first time and performing a task of resolving the jamming after the user has instructed the image formation causes a problem in terms of operability and user-friendliness.
Also, a case is possible in which the user resolves jamming by removing the paper jamming that is the cause of the jamming when the image forming apparatus is in a powered-off state. In such a case, since the jamming has already been resolved when the image forming apparatus is powered on the next time, it is desirable that no notification of jamming is made. Because of this, it is necessary to detect that jamming has not occurred using the jam detection sensor when the image forming apparatus is powered on. However, with an image forming apparatus that is started up without the engine unit being energized, detection using the jam detection sensor cannot be performed at the time of startup, and therefore there is a problem in that accurate jam information cannot be notified to the user.